Method for making chrome-steel



UNITED STATES PATENT OFFICE.

HUGH C. SICARD, OF BUFFALO, NEW YORK, ASSIGNOR T0 UNITED STATES FERRO- ALLOYS CORPORATION, OF NEW YORK, N. Y. A CORPORATION OF NEW YORK.

METHOD FOR MAKING CHROME-STEEL.

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No Drawing.

To all whom it may concern Be it known that I, HUGH C. SICARD, a citizen of the United States of America, and a resident of the city of Buffalo, county of Erie, and State of New York, have invented certain new and useful Improvements in Methods for Making Chrome- Steel, of which the following is a full, clear, and exact description.

This invention relates generally to the manufacture of chrome steel, that is, a steel containing various proportions of chromium.

More particularly this invention relates to making additions of ferro-chrome to steel and consists in a novel method whereby the process of manufacture can be carried on with much greater ease and with more certainfilzy of obtaining the quality of steel desire It is well known to the art that when a chromium addition is made to various grades of steel, it is sometimes hard to control, in a close range, the chromium content of the steel. It is recognized that a varying amount of chromium is lost mostly by oxidation with a more or less oxidized molten steel bath. This will occur even if attempts have been made to previously deoxidize such bath by the addition of a deoxidizer such as, for instance, the addition of 50% ferrosilicon.

I am aware that several attempts in the art have been made to provide alloys for the deoxidation of steel and inparticular for the use of titanium and that in some instances ferro chrome additions have been made by placingsuch additions into the fur- Serial No. 318,332.

nace when the molten steel is in a state of oxidation. I

I have discovered, after close examina tions of the slag resulting from such operations, that there is a certain amount of chromium oxid contained in the slag. A careful investigation shows that this chromium has been oxidized by contact with the oxids in the molten steel.

In carrying out my invention, I use a ferro-chromium-titanium alloy which is really a complex carbid of chromium, iron and titanium. The titanium present in this alloy is very readily oxidizable. It will oxidize, protecting the chromium, and consequently will allow the steel manufacturer to get a more accurate yield in his chromium addition. Thus the greater part of the chromium alloys with the steel instead of reactin with the oxids.

aving thus described my invention, what I claim is:

1. An improved process for making chro- -mium steel whichconsists in adding to molten steel an alloy of iron, chromium, titanium and carbon.

2. An improved process for making'chromium steel which consists in adding to molten steel a complex carbid of chromium, 1ron and titanium. t

3.- An improved process for making chromium steel which consists in adding to mo1-' ten steel, a ferro-chromium-titanium alloy combined with carbon.

In testimony whereof I. have hereunto signed my name.

HUGH o. SICARD.

Patented July 13, 1920. 

